Marine Water Tanks

These NSF and FDA compliant marine water storage tanks are made to be incredibly strong, nearly unbreakable, and are very affordable. Plastic marine water tanks (poly) are available in nearly every size and shape. Made from one piece of thick poly, there are no seams so less opportunity for leaking, and made with a rotomold process for superior strength. You won’t find better-made marine fresh water tanks for the price. 

Made from one piece to form 3/8” thick walls using a roto-mold process to create a seamless holding tank superior in strength and performance. These custom fitted marine water tanks are built to go the distance.   

*Note: Customize the placement of the fittings when you place the order.  We spin-weld the fittings to ensure your holding tank is securely connected to your plumbing.

  • Complies with NSF 61, FDA Reg CFR 177.1520, and Coast Guard Standards
  • Made from virgin polyethylene (poly) resins
  • Seamless tank made from one piece (less likely to break or leak)
  • 3/8” thick tank walls
  • Customized fitting placement
  • Spin weld fittings
  • Outlasts the competition

For use as marine water tanks, marine fresh water tanks, plastic marine water tanks, poly marine water tanks, custom marine water tanks, and more!

We have 100’s of sizes ranging from 2 gallons, 40 gallons, 50 gallons, 100 gallon marine water tanks.  They range in size up to 250 gallons for these poly marine fresh water tanks.

Looking for something else? Chances are, we have it, and at affordable prices too!  Just call us and ask!

Pick the size and shape you need from the list. Mark up the drawing with your fittings placement. Call us with any questions!

Marine Water Tanks

  • 95 Gallon Marine Water Tank MW-230. Technical drawing of a polyethylene water tank designed for marine vessels.

    95 Gallon Marine Water Tank MW-230

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 95 Gallon Marine Water Tank, Part# MW-230, is engineered to meet the requirements of mobile...

    MSRP: $819.96
    $779.60
    Add to Cart
  • 95 Gallon Marine Water Tank MW-218. Technical drawing of a polyethylene water tank designed for marine vessels.

    95 Gallon Marine Water Tank MW-218

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 95 Gallon Marine Water Tank, Part# MW-218, is engineered to meet the requirements of mobile...

    MSRP: $501.60
    $476.90
    Add to Cart
  • An image of a 7 Gallon RV Fresh Water Tank | RVB326

    97 Gallon Marine Fresh Water Tank | B487

    Introducing the 97 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is specifically designed for marine use, making it perfect for boats and other water vessels. With its rectangular shape, it can easily fit in tight spaces and maximize...

    $689.91
    Add to Cart
  • 97 Gallon Marine Water Tank MW-303. Technical drawing of a polyethylene water tank designed for marine vessels.

    97 Gallon Marine Water Tank MW-303

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 97 Gallon Marine Water Tank, Part# MW-303, is engineered to meet the requirements of mobile...

    MSRP: $682.40
    $648.81
    Add to Cart
  • An image of a 60 Gallon Marine Holding Tank | BOAT54W

    98 Gallon Marine Fresh Water Tank | B530

    Introducing the 98 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is specifically designed for marine use, making it perfect for boating and other water activities. With its rectangular shape, it offers a space-efficient solution for...

    $935.95
    Add to Cart
  • An image of a 25 Gallon RV Holding Tank | RV31H

    98 Gallon Marine Fresh Water Tank | B477

    The 98 Gallon Marine Fresh Water Tank by One Clarion is a rectangular-shaped portable tank designed for above ground use. This tank is made of polyethylene material in a natural white color, measuring 35 inches in length, 27 inches in width, and 26...

    $783.30
    Add to Cart
  • 98 Gallon Marine Water Tank MW-214. Technical drawing of a polyethylene water tank designed for marine vessels.

    98 Gallon Marine Water Tank MW-214

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 98 Gallon Marine Water Tank, Part# MW-214, is engineered to meet the requirements of mobile...

    MSRP: $556.72
    $529.32
    Add to Cart
  • 99 Gallon Marine Water Tank MW-554. Technical drawing of a polyethylene water tank designed for marine vessels.

    99 Gallon Marine Water Tank MW-554

    This tank ships in 6-8 weeks. Custom fitting placement is not available at this time. It can be ordered blank, or blank with a DIY Fitting Kit Custom Roto-Mold 99 Gallon Marine Water Tank, Part# MW-554, is engineered to meet the requirements of mobile...

    MSRP: $725.31
    $689.61
    Add to Cart
  • An image of a 7 Gallon Marine Fresh Water Tank | B535

    100 Gallon Marine Fresh Water Tank | B455

    Introducing the 100 Gallon Marine Fresh Water Tank by One Clarion. This rectangular tank is designed specifically for marine use, making it the perfect choice for boat owners and enthusiasts. With its portable design, you can easily transport and install...

    $689.91
    Add to Cart
  • An image of a 36 Gallon RV Fresh Water Tank | RVB254

    100 Gallon Marine Fresh Water Tank | B426

    Introducing the 100 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is specifically designed for marine use, making it perfect for boats and other water vessels. With a rectangular shape and a capacity of 100 gallons, this tank provides...

    $912.86
    Add to Cart
  • An image of a 53 Gallon RV Fresh Water Tank | RVB312

    100 Gallon Marine Fresh Water Tank | B400

    Introducing the 100 Gallon Marine Fresh Water Tank by One Clarion. This portable tank is designed specifically for marine use, making it the perfect solution for your fresh water needs on your boat or yacht. With a rectangular shape and a capacity of 100...

    $912.86
    Add to Cart
  • An image of a 45 Gallon RV Fresh Water Tank | RVB310

    100 Gallon Marine Fresh Water Tank | B313

    The 100 Gallon Marine Fresh Water Tank by One Clarion is a rectangular-shaped portable tank designed for above ground use. This tank is made of polyethylene material in a natural white color and measures 48 inches in length, 37 inches in width, and 20...

    $1,065.50
    Add to Cart